1. Field of the Invention
This invention relates to optical projection systems, and particularly to a system which enables a viewer to perceive all three dimensions of an enlargement of a three-dimensional object or recorded scene.
2. General Description of the Prior Art
There have been several attempts in the past to reproduce images in three dimensions. The first known one utilized stereopsis wherein the eyes of a viewer separately viewed two photographs taken from slightly different angles. Several methods have been used in the past utilizing this approach for projecting three-demensionally appearing movies on a large screen for audience viewing. One of these methods utilized two images projected onto a screen, one being filtered red and the other filtered blue. The viewer would then wear glasses with one lens colored red to filter out the red image, and the other lens colored blue to filter out the blue image. Thus, each eye would perceive a different image of the projection, and thus the three-dimensional or stereopsis effect.
Another and similar method separates the images by polarization, one image being polarized perpendicular to the other image, with the viewer wearing glasses with a polarized lens.
A more recent system utilizing the stereopsis effect does away with the glasses, utilizing a lenticular screen which projects two images selectively to different zones of a theater. The limitation of this system is that the viewer may not move his head very far in either direction without losing the stereoptical effect or the image entirely.
Another and still more recent projection system utilizes a cylindrical lens arrangement for the recording and projection of a hologram. While with this system a viewer may move from side to side in a longitudinal plane without losing a parallex effect provided by this system, the effect is limited to parallex in the longitudinal plane, and the final projected image would be the same size as the object from which the hologram is made if no longitudinal distortion is to be introduced. No vertical parallex is achievable with this system, and thus its three-dimensional effect is limited.